[SOLVED] i5-8265U Core Clock keeps dropping significantly.

[TrustButVerify]

Hello,

As the title says, my (laptop) CPU keeps dropping in "constant" intervals under load.

I took this screenshot while playing rocket league. Every single time the CPU usage drops, I get a quick but huge fps drop from 60 to 20-5 fps.
Min and Max cpu usage in windows power plan are both set to 100%. My temps are also good so it can't be throttling.
It does the same thing in other low demanding games like Unturned and Brawlhalla.
Are there any solutions to this or answers to 'why' it actually does it?
System specs:
HP Pavilion 15-cs3147nb:
i5-8265U 1,6 Ghz
8GB Memory
Nvidia Geforce MX250 2 GB

 

[rgd1101]

and the gpu usage?

 

[TrustButVerify]

and the gpu usage?

Hi, sorry for the late response.
GPU usage has these ups and downs too (in sync with the CPU) as seen down here. I guess the GPU is getting bottlenecked by the CPU.
Also when the CPU usage drops, the core clock drops to around 0.40 Ghz.
I also added my memory usage, but it never runs out of memory.
The last image are my CPU temps which are still not high enough for any throttling. It also displays power, which drops to about 3-4 Watts when usage drops.

 

[TrustButVerify]

I hope this will help:
I tried testing my CPU with cinebench. The results are just more evidence that it's my CPU to blame. GPU wasn't used at all. For some weird reason tho, the single core test is stable and does't have these usage drops.

Multi-core Test :
Again the usage and core clock drops. Also the constant intervals just weird me out.

Single-core test:

 

[ragnarok0274]

Bad core maybe?
I am totally an expert in this subject and am not guessing.

 

[erayrafet]

Hey!
I do have an HP Pavilion 13-AN007NU with the exact same CPU and the same problem where the core clock locks to a constant 400 MHz even under moderate load, and to fix I need to plug the charger in. Similarly, sometimes the CPU speed stays at 800, or just today at 1500 MHz and no matter what it won't go higher.
No thermal throttling is observed.

 

[TrustButVerify]

PROBLEM FIXED!

A faulty charger was the devil! I found out (by luck) that every time while charging, my CPU's core clock dropped leading to frame drops / screen freezes in games and just slow performance in programs. When unplugging the charger (using battery) everything was completely normal and stable. I ordered a new charger that worked perfectly fine without any instability.

I kept switching between the new and old charger and every time the older one was indeed the problem for the instability.

 

[TrustButVerify]

Hey!
I do have an HP Pavilion 13-AN007NU with the exact same CPU and the same problem where the core clock locks to a constant 400 MHz even under moderate load, and to fix I need to plug the charger in. Similarly, sometimes the CPU speed stays at 800, or just today at 1500 MHz and no matter what it won't go higher.
No thermal throttling is observed.

Hi!
The problem had indeed something to do with my charger. Only I had kept using a faulty charger leading to these instabilities. I ordered a new charger and everything worked perfectly.

 

[erayrafet]

Hi!
The problem had indeed something to do with my charger. Only I had kept using a faulty charger leading to these instabilities. I ordered a new charger and everything worked perfectly.

Well, I get that weird behavior when running on battery, but it is still rock solid so I think there's something deeper that's the cause.

 

[erayrafet]

Here's a screenshot. It became slow after I woke up the machine from hibernation. I wonder if that's causing it.
https://drive.google.com/file/d/1BoORkMFyNpMtoDbh91KjGsa60dtJwAp-/view?usp=sharing